1. Field of the Inventioin
The present invention relates to a disk driving apparatus. More particularly, the present invention relates to a disk driving apparatus for recording data in and reproducing data from a disk-type storage medium (hereinafter, simply referred to as xe2x80x9ca diskxe2x80x9d), the disk driving apparatus having a simple structure for (i) inserting therein and ejecting therefrom a tray on which the disk is placed and (ii) ascending and descending a recording/reproducing head relative to the disk, in connection with the movement of the tray.
2. Description of the Related Art
Current generally used recording/reproduction apparatus for a disk, or a storage medium operates insertion and ejection of the disk as follows. First, the disk is set on a tray projecting out from the apparatus. The tray is then slid into the apparatus, whereby a head base unit supporting a rotation table, a disk motor and an optical head ascends so that the disk is placed on the rotation table. Thus, the disk is separated from the tray and is carried up to an upper position at which recording/reproduction is performed by the optical head. Moreover, the disk is ejected by performing the above-described steps in reversed order.
The above-described disk driving apparatus mainly has two activities, i.e., inserting and ejecting the tray, with or without the disk, into and from the apparatus and ascending and descending the head base unit in connection with the insertion and ejection of the tray.
With the recent remarkable spread of CDs, CD-ROMs and the like, minimization and lower production cost of the disk driving apparatus are greatly demanded. In order to meet such demands, it is necessary to perform the above-described two main activities with a single driving power source.
Japanese Patent Application No. 3-292964 and Japanese Laid-Open Publication No. 5-182335 disclose examples of disk driving apparatuses having such a structure.
Specifically, such a disk driving apparatus generally includes a loading driving power source, a head base unit with a pin provided on its tip, a rotation body having a cam groove that engages with the pin of the head base unit, an intermediate gear which shares a rotating shaft with the rotation body, a planetary gear being engaged with the intermediate gear and supported by the tip of the rotating shaft of the rotation body so as to be revolvable around a sun gear and rotatable on its axis and a tray provided with a U-shaped rack. The rotation body reciprocally rotates so as to ascend and descend the head base unit. The intermediate gear is rotationally driven by the loading driving power source. In the case where the tray is conveyed, the planetary gear rotates along a linear portion of the U-shaped rack. Once the tray reaches the deepest closed position of the apparatus, the planetary gear starts to revolve and rotate, together with the rotation body, along a curved portion of the U-shaped rack. The rotation of the rotation body forces the head base unit to ascend, whereby the disk driving apparatus is ready for recording/reproducing.
Furthermore, a lock structure is also disclosed in the above-mentioned publications which prevents the rotation body from revolving around the sun gear during the conveyance of the tray.
According to the above-described structure, however, the tray may forcibly be halted by an operator or other factors while it is projecting out from the disk driving apparatus, or the tray may forcibly be pulled out from or pushed into the disk driving apparatus. In these cases, no matter how firm the lock for the rotation body is made, the lock of the rotation body may come off. As a result, the rotation body may revolve around the sun gear before the tray reaches the deepest closed position of the disk driving apparatus which, in some cases, results in contact of the head or the rotation table with the tray. Accordingly, there are problems of breaking the head and deteriorating the profile irregularity of the rotating table.
Moreover, according to the above-described structure, the head base unit is supported only at one point where the pin at the tip thereof and the cam groove of the rotation body engage with each other. Therefore, for example, when the disk driving apparatus is dropped on a floor, an impact load on the whole head base unit is concentrated on the single supporting point. As a result, there may also be problems of damage or distortion of the cam groove of the rotation body or the pin of the head base unit.
According to one aspect of the present invention, a disk driving apparatus includes: a head base unit which supports a head for recording data into and reproducing data from a storage medium, the head base unit being able to travel between a first position where the head is close to the storage medium for recording data thereto and reproducing data therefrom and a second position where the head is apart from the storage medium; a tray provided with a tray rack extending in a predetermined direction, the tray being slidable along the tray rack between a third position at which the head performs recording and reproduction on the storage medium and a fourth position at which an operator can place the storage medium; a driving power source; a tray gear which is driven by the driving power source; a rotation body gear which is driven by the driving power source; a partial gear which partially engages with the rotation body gear at a predetermined angle; and a rotation body which, in accordance with the rotation of the partial gear, reciprocally rotates so that the head base unit travels between the first position and the second position. When the tray is present at the third position, the tray gear is apart from the tray rack. Moreover, the rotation body includes a rotation body engagement section which engages with the tray while the tray travels from the third position to a predetermined position. Furthermore, the rotation body further includes a rotation body protrusion which pushes the tray substantially in the same direction as the sliding direction of the tray such that the tray gear engages with the tray rack while the tray is travelling between the third position and the fourth position.
In one embodiment of the present invention, a ratio of the number of teeth of the tray gear and the number of teeth of the rotation body gear is an integer.
According to another aspect of the present invention, a disk driving apparatus includes: a head base unit which supports a head for recording data into and reproducing data from a storage medium, the head base unit being able to travel between a first position where the head is close to the storage medium for recording data thereto and reproducing data therefrom and a second position where the head is apart from the storage medium; a tray provided with a tray rack extending in a predetermined direction, the tray being slidable along the tray rack between a third position at which the head performs recording and reproduction on the storage medium and a fourth position at which an operator can place the storage medium; a driving power source; a tray gear which is driven by the driving power source; a rotation body gear which is driven by the driving power source; a partial gear which partially engages with the rotation body gear at a predetermined angle; a rotation body which, in accordance with the rotation of the partial gear, reciprocally rotates so that the head base unit travels between the first position and the second position; a rotation body lock portion provided for the rotation body, which locks the rotation movement of the rotation body while maintaining the head base unit at the second position; and an unlock portion provided for the tray, which acts on the rotation body lock portion so as to allow rotation of the rotation body.
In accordance with one embodiment of the present invention, the rotation body lock portion includes an elastic portion integrally provided for the rotation body and a lock detent provided on a tip of the elastic portion, which is detachable from a hook provided for a main body. The unlock portion releases the engagement between the lock detent and the hook by pushing the lock detent while the tray is inserted into the disk driving apparatus.
In accordance with another embodiment of the present invention, the unlock portion rotates the rotation body at the engagement between the tray and the rotation body in a direction where the lock detent departs from the hook, immediately before the locking of the lock detent during the ejection of the tray or immediately before the unlocking of the lock detent during the insertion of the tray.
According to still another aspect of the present invention, a disk driving apparatus includes: a head base unit which supports a head for recording data into and reproducing data from a storage medium, the head base unit being able to travel between a first position where the head is close to the storage medium for recording data thereto and reproducing data therefrom and a second position where the head is apart from the storage medium; a tray provided with a tray rack extending in a predetermined direction, the tray being slidable along the tray rack between a third position at which the head performs recording and reproduction on the storage medium and a fourth position at which an operator can place the storage medium; a rotation body which makes the head base unit travel between the first position and the second position; a rotation plane provided integrally with the rotation body on a plane that intersects with a rotation shaft of the rotation body at right angle; a rotation concave portion provided for part of the rotation plane; a lock concave portion provided for the main body; a head base supporting body which supports the head base unit at the first position; head base supporting faces provided for parts of the head base supporting body and slips under the head base unit, thereby supporting the head base unit at the first position; a lock convex portion provided for the head base supporting body, which has elasticity and is detachable from the lock concave portion of the main body; and a rotation convex portion integrally provided with the lock convex portion, which is detachable from the rotation concave portion of the rotation body. The head base supporting body is resting while the rotation body is rotated so as to make the head base unit travel from the first position to the second position since the rotation convex portion is pushed by the rotation plane and the lock convex portion is engaged with the lock concave portion. When the head base unit completes travelling, the rotation concave portion engages with the rotation convex portion and the head base supporting body travels together with the rotation body so that the head base supporting faces slip under the head base unit, thereby supporting the head base unit.
In accordance with one embodiment of the present invention, the head base supporting faces start to slip under the head base unit while the head base unit is lifted higher than the first position by the rotation body. The head base unit and the rotation body are structured such that after the head base unit is moved by the rotation body and placed on the head base supporting faces, the engagement between the head base unit and the rotation body is released.
In accordance with another embodiment of the present invention, the tray engages with the rotation body at the second position. After making the head base unit travel from the first position to the second position, the rotation body is able to eject the tray for a predetermined distance via the engagement section between the rotation body and the tray. The rotation body is provided with an operation lever which is exposed so as to allow operation thereof from outside the main body. The operation lever is engaged with the main body and has a shape such that force on the main body, which is received from the rotation convex portion caused by elasticity of the head base supporting body is controlled.
In accordance with still another embodiment of the present invention, each of portions of the head base supporting faces where they first slip under the head base unit is provided with a guiding shape.
In accordance with still yet another embodiment of the present invention, each of portions of the head base unit where the head base supporting faces first slip is provided with a guiding shape.
According to still yet another aspect of the present invention, a disk driving apparatus includes: a head base unit which supports a head for recording data into and reproducing data from a storage medium, the head base unit being able to travel between a first position where the head is close to the storage medium for recording data thereto and reproducing data therefrom and a second position where the head is apart from the storage medium; a tray provided with a tray rack extending in a predetermined direction, the tray being slidable along the tray rack between a third position at which the head performs recording and reproduction on the storage medium and a fourth position at which an operator can place the storage medium; a first lateral tray regulating wall provided for the tray in a parallel direction with respect to the sliding direction; a second lateral tray regulating wall provided in a parallel direction with respect to the sliding direction so as to oppose to the first lateral tray regulating wall; a concave shaped tapered regulation releasing portion provided for the second lateral tray regulating wall; a first lateral guiding portion and a second lateral guiding portion provided next to each other in a direction of sliding of the tray, both of the first lateral guiding portion and the second lateral guiding portion making contact with the first lateral tray regulating wall; lateral protrusions which, between the first lateral guiding portion and the second lateral guiding portion, press the first lateral tray regulating wall and the second lateral tray regulating wall against the first lateral guiding portion and the second lateral guiding portion; a driving power source; a tray gear driven by the driving power source; a rotation body gear driven by the driving power source; a partial gear partially engaged with the rotation body gear at a predetermined angle; and a rotation body which reciprocally rotates, in accordance with the rotation of the partial gear so as to make the head base unit travel between the first position and the second position. When the tray is present at the third position, the position of the tapered regulation releasing portion matches with the position of the lateral protrusion so that the pressure of the lateral protrusion on the second lateral tray regulating wall is released. In the ejection step where the rotation body which is rotationally driven by the rotation body gear, makes the tray conveyed forward at the engagement between rotation body and the tray so that the tray rack is engaged with the tray gear, the position of the tapered regulation releasing portion is shifted from the position of the lateral protrusion, immediately before the tray rack is engaged with the tray gear, whereby the lateral protrusion presses the second lateral tray regulating wall.
In accordance with one embodiment of the present invention, a ratio of the number of teeth of the tray gear and the number of teeth of the rotation body gear is an integer.
According to one aspect of the present invention, the tray is resting when the end of the tray rack is separated from the tray gear. Due to the engagement between the rotation body gear and the partial gear partially provided with teeth, the rotation body is rotationally driven by the rotation body gear driven by the driving power source so that the rotation body moves the head base unit from the first position. The rotation protrusion of the rotation body driven by the rotation body gear pushes the tray, thereby engaging the tray rack and the tray gear.
Due to the engagement between the tray rack and the tray gear, the tray is driven by the tray gear and starts to move. The rotation body is driven, at the rotation body protrusion engaging with the tray and the partial gear partially provided with teeth, by both the tray and the rotation body.
The rotation body is separated from the rotation body gear and is driven only by the tray at the rotation body protrusion. The engagement between the rotation body and the tray is released, whereby only the tray is ejected to the fourth position by the tray gear.
Therefore, when the tray is projecting out from the apparatus, the rotation body gear of the tray driving system is separated from the rotation body. Accordingly, even when the tray is forcibly halted by an operator or other factors while it is projecting out from the disk driving apparatus, or the tray is forcibly pulled out from or pushed into the disk driving apparatus, the rotation body for ascending and descending the head base unit is not affected at all and stays at the predetermined position.
According to another aspect of the present invention, the tray is resting when the end of the tray rack is separated from the tray gear. Due to the engagement between the rotation body gear and the partial gear partially provided with teeth, the rotation body is rotationally driven by the rotation body gear driven by the driving power source so that the rotation body moves the head base unit from the first position. The rotation protrusion of the rotation body driven by the rotation body gear pushes the tray, thereby engaging the tray rack and the tray gear.
Due to the engagement between the tray rack and the tray gear, the tray is driven by the tray gear and starts to move. The rotation body is driven, at the rotation body protrusion engaging with the tray and the partial gear partially provided with teeth, by both the tray and the rotation body.
The rotation body is separated from the rotation body gear and is driven only by the tray at the rotation body protrusion.
The rotation body lock portion holds the rotation movement of the rotation body.
The engagement between the rotation body and the tray is released, whereby only the tray is ejected to the fourth position by the tray gear.
According to still another aspect of the present invention, during the process of moving the head base unit to the second position by the rotation body, the rotation convex portion is pushed by the rotation plane and the lock convex portion is engaged with the lock concave portion. Thus, the head base unit supporting body is resting.
The rotation concave portion engages with the rotation convex portion when the head base unit is completely transferred. The head base supporting body travels together with the rotation body. The head base supporting faces slip under the head base unit, whereby the head base supporting body supports the head base unit.
Therefore, the head base supporting body which is intermittently engaged to be driven by the rotation body supports the head base unit by two supporting faces thereof, thereby increasing the area for supporting the head base unit. Accordingly, damage caused by impact on the disk driving apparatus (e.g., dropping on the floor) can be greatly minimized.
According to still yet another aspect of the present invention, when the tray is present at the third position, the position of the tapered regulation releasing portion is matched with the position of the lateral protrusion. The pressure of the lateral protrusion on the second lateral tray regulating wall is released.
When the rotation body which is rotationally driven by the rotation body gear moves the tray to the fourth position at the engagement section therebetween, the tray rack engages with the tray gear. The position of the tapered regulation releasing portion is shifted from the position of the lateral protrusion immediately before the tray rack engages the tray gear. As a result, the lateral protrusion presses the second lateral tray regulating wall.
Accordingly, lateral vibration of the tray during the ejection of the tray can be decreased. As a result, the end tooth of the tray rack can be engaged with the correct tooth of the tray gear, thereby realizing stable traveling of the tray.
Thus, the invention described herein makes possible the advantage of providing a disk driving apparatus in which an ascending/descending activities of the head base unit are not affected even if the tray projecting out from the disk driving apparatus is roughly operated, and the head base unit or a rotation body are not damaged or distorted by impact on the disk driving apparatus, for example, by being dropped.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.